Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Nutrition I - Semester 2 Need To Know > Proteins > Flashcards

Proteins Flashcards

1
Q

Body Composition

A

Protein ~20% (17%)
Water 65%
Fat 10%
Minerals 4%
Carbohydrates 1%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Protein Chemical Structure

A

• Proteins are organic compounds that contain Carbon, Hydrogen, Oxygen and Nitrogen.
• The presence of Nitrogen distinguishes proteins from fats and carbohydrates.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Amino Acid Components

A

• Amino acids are the basic building blocks of proteins. Each amino acid contains:
- An amino group NH 2
- A carboxylic acid group COOH
- A unique side group ( R group ) which differentiates amino
• There are approximately 1000 amino acids in nature.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Non- Essential AA’s

A

Alanine
Aspartic acid
Glutamic acid
Serine
Asparagine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Essential AA’s

A

Phenylalanine
Valine
Threonine
Tryptophan
Isoleucine
Methionine
Histidine
Leucine
Lysine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Essential AA’s Pneumonic

A

PVT TIM HiLL

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Conditionally Essential AA’s

A

Arginine
Cysteine
Glutamine
Glycine
Proline
Tyrosine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Glutamine

A

• Glutamine is the most abundant amino acid in the body, containing 60% of the total pool of free amino acids.
• It is the preferred fuel for rapidly dividing cells such as enterocytes (gut support), lymphocytes and macrophages (immunity)
• The body’s glutamine synthesis becomes unable to meet higher requirements during acute stress , and hence it is considered conditionally essential . Stress states include injury (for wound healing) and infections (for supporting the immune response).
• It behaves as a buffer, receiving excess ammonia (i.e. nitrogen), before releasing it when needed to form other amino acids (e.g. arginine) and nucleic acids.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Glutamine and the Intestinal Barrier

A

• Glutamine is the primary amino acid source for intestinal cells and helps to regulate tight junction integrity and enterocyte proliferation. Depletion results in decreased expression of tight junction proteins and increased intestinal permeability.
• Increased intestinal permeability causes include coeliac disease, IBD, candidiasis,
alcohol, SIBO, food allergies / intolerances, chronic stress , nutrient deficiencies (e.g. glutamine, zinc), NSAIDs , chemotherapy .
• Intestinal permeability leads to the leakage of LPS into the blood, which can lead to various chronic diseases, e.g. autoimmunity.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Support for Leaky Gut

A

• Glutamine supplementation (10g per day)
• Glutamine rich foods e.g. cabbage juice (1L fresh juice taken over the day for 10 days), spirulina, asparagus, broccoli, cod, salmon.
• N-acetyl glucosamine (support mucosal integrity) in shellfish.
• Quercetin (apples, red onion, tomatoes, red peppers)
• Zinc (for rapid cell division and tight junction support)
• Antioxidants (e.g. vitamin C, E and beta carotene).
• Herbs: Turmeric, Marshmallow, Slippery Elm, Goldenseal, Myrrh.
• Bone broth (rich in collagen, glucosamine, chondroitin, glycine).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Glutamine Functions

A

Immunity
Hypoglycaemia
Muscle Recovery
Neurotransmitter

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Glutamine: Supplementation Drug Interactions

A

Anti-seizure medications e.g. phenobarbital, phenytoin, carbamazepine, primidone and valproic acid.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Glutamine: Supplementation Toxicity

A

No adverse effects reported during short-term dosing up to 50-60g/day.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Glutamine: Supplementation Caution

A

Cancer cells can use glutamine to fuel their growth and metabolism so use alternative gut repair remedies in cancer care. Avoid in cases of epilepsy. Also caution in liver or kidney disease.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Cysteine

A

• Cysteine is a conditionally essential amino acid formed from methionine and serine in the liver (B6, B9 and B12 are needed).
• Direct food sources (most sulphur in food is in the form of protein bound cysteine): legumes, sunflower seeds, eggs, chicken
• It is a component of glutathione and is needed in the formation of Co-enzyme A and taurine
• It is the rate limiting amino acid for glutathione synthesis, so is very important for detoxification and antioxidant support.
• Cysteine is the source of sulphate (-SO 4 ), used in the phase II liver detoxification pathway sulfation (used for many drugs, steroid hormones etc.) increasing water solubility for their excretion.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

N- Acetyl Cysteine Functions

A

Liver Detoxificationn/ Antioxidant
Reproductive Health
Respiratory Health
Insulin Resistance

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

N-Acetyl Cysteine: Other applications

A

In emergency medicine, NAC is used as an antidote for paracetamol toxicity resulting from an overdose (as paracetamol is detoxified using the glutathione pathway) protecting the liver from damage.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

N-Acetyl Cysteine: Drug Interactions

A

Nitro glycerine (can cause hypotension and headaches).
Caution also with insulin use.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Methionine

A

Methionine is a sulphur containing essential amino acid.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Methionine: Food Sources

A

High in animal foods Beef, eggs, chicken etc. Brazil nuts, sunflower seeds, beans, whole grains (e.g. quinoa).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Methionine: Functions

A

Methionine is a major methyl donor in the body (for methylation reactions such as the homocysteine cycle, and in phase 2 liver detoxification). Raised homocysteine damages the vascular endothelium and increases the risk of atherosclerosis and miscarriage.
- Use B6, folate and B12 to support methylation, whilst restricting dietary methionine (animal sources) to lower homocysteine.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Methionine: Caution

A

Excess methionine also increases acidity in the body.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Carnitine

A

• Carnitine is an amino acid derivative that can be obtained from the diet or synthesised in the body from methionine and lysine. This production requires iron, vitamin C, B3, B6.
• Deficiency of carnitine (rare) results primarily from errors of metabolism, and not from insufficient dietary intake, as the body is usually able to synthesise adequate quantities
• Mutations of the ‘SLC22A5’ gene can make it a conditionally essential amino acid.
• Direct food sources: nuts, seeds, avocado, asparagus, spinach, red meats, dairy.
• Carnitine acts as a peripheral thyroid hormone antagonist, so it can be used therapeutically in cases of hyperthyroidism.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Carnitine: Functions

A

Assists ATP synthesis from fatty acids

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Carnitine Supplementation: Drug Interaction

A

Supplementing carnitine alongside anticoagulants (e.g. warfarin) increases the blood thinning effects.
Thyroid hormones due to carnitine’s effects as a peripheral thyroid hormone antagonist, and thus high dose carnitine is contraindicated with hypothyroidism.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Carnitine Supplementation: Caution

A

L-carnitine use has been associated with nausea, vomiting, abdominal cramps, heartburn, gastritis, diarrhoea, body odour and seizures, but only at high doses . One of its metabolites
can cause the urine, breath and sweat to have a fishy odour.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Creatine

A

• Creatine is a small peptide made of the amino acids arginine, glycine and methionine. It is formed in the liver, kidneys and pancreas.
• About 95% of body creatine is found in muscles (with some also in the brain), and functions as a fast source of ATP in the form of ‘creatine phosphate’.
• Creatine supplementation was first introduced to the public in the 1990s after Olympic athletes were reported to be using it to improve performance.
• Direct food sources (it can be obtained from the diet, but is otherwise created by the body): meat, fish and eggs.

28
Q

Creatine Functions

A

A storage form of ATP (energy)

29
Q

Creatine: Drug Interactions

A

Combining caffeine, ephedra and creatine may lead to ischaemic stroke. High doses of creatine might affect renal function and combining creatine with nephrotoxic drugs (e.g. NSAIDs, some antibiotics) might have other harmful effects on kidney function.

30
Q

Creatine: Caution

A

Creatine can cause abdominal pain, nausea, diarrhoea, palpitations and muscle cramping. Creatine causes muscles to draw water from the rest of your body (also causing people to gain weight) hydration is important!

31
Q

Glycine

A

• Glycine is a conditionally essential amino acid in the case of certain metabolic stresses. For example:
– Increased haem synthesis for blood formation.
– Collagen formation for growth and repair.
– Glycine conjugation in detoxification.
– Glycine is made with the help of serine and vitamin B6, so if either of these are in short supply so is glycine!
• Food sources: legumes, seaweed, spinach, kale, cauliflower, cabbage, banana, pumpkin, bone broth, meat, fish, eggs.
• Glycine is required for the synthesis of haem, DNA, RNA, bile acids, glutathione (for liver detox), creatine, skin and connective tissue.

32
Q

Glycine: Functions

A

Collagen Synthesis
Liver Detox
Neurotransmitters

33
Q

Taurine

A

• Taurine is a conditionally essential amino acid that is normally synthesised in the body in adequate amounts from cysteine with the help of vitamin B6.
• During times of extreme stress and illness the body may be unable to produce taurine, so supplementation may be needed.
• Direct food sources: only in animal sourced food (especially chicken / turkey thighs and fish). It is also in breast milk.
• Supplementation is necessary in non breastfed infants because their ability to synthesise taurine is undeveloped and cow’s milk does not provide a sufficient amount. Taurine is often added to human infant formulas.

34
Q

Taurine: Functions

A

Muscle Health
Antioxidant
Neurological
Bile
Insulin

35
Q

Taurine: Drug Interactions

A

Lithium, may decrease excretion.
Blood pressure medications, may cause additive effect.

36
Q

Taurine: Contraindicated

A

Bipolar disorder as it may worsen symptoms.

37
Q

Taurine: Caution

A

Taurine is added to some energy drinks in an effort to harness its benefits. This is NOT a good source of taurine, as they often contain refined sugars, caffeine, artificial sweeteners etc.

38
Q

Theanine

A

• Theanine is not one of the 20 amino acids needed for body structure, but has various beneficial effects. It is non-essential..
• It is the amino acid found uniquely in green tea. Theanine is believed to give green tea its slight umami flavour and helps to counteract the bitterness of green (and black) tea.
• Theanine reduces the negative effects of caffeine naturally in green tea by having opposing effects (relaxing rather than stimulating).
• The theanine content in green tea is one of the reasons the beverage is considered therapeutic in Ayurvedic medicine, due to its balancing effects especially for those who are restless / anxious.

39
Q

Theanine: Functions

A

Neurological Calming

40
Q

Theanine: Therapeutic Uses

A

Therapeutic Uses
• Studying / increasing concentration.
• Anxiety/agitation (including that associated with PMS)
• Stress
• Insomnia
• Low mood
• Hypertension

41
Q

Theanine: Drug Interactions

A

Theanine can lower blood pressure, so avoid using alongside anti hypertensives or it may fall too low.

42
Q

Theanine: Adverse effects

A

Theanine may cause mild adverse effects, such as headache or sleepiness.

43
Q

Tyrosine

A

• Tyrosine is a conditionally essential amino acid derived from phenylalanine.
• Food sources: nuts, seeds, legumes, whole grains (e.g. quinoa, oats), fish, meat, poultry.

44
Q

Tyrosine: Functions

A

Endocrine Health

Functions:
• Tyrosine is a precursor to the thyroid hormones, dopamine, epinephrine (adrenaline), norepinephrine (noradrenaline).
• It is also a precursor to melanin (the skin pigment)

Therapeutic Uses:
• Adrenal fatigue
• Hypothyroidism
• ADHD
• Depression
• Anxiety
• Cognition

45
Q

Tyrosine: Dosage

A

400-6000mg/day. Tyrosine seems to be safe when used in doses up to 150 mg/kg per day for up to 3 months.

46
Q

Tyrosine: Drug Interactions

A

MAOI antidepressants (the enzyme MAO deactivates dopamine etc.), Levodopa, thyroxine.

47
Q

Tyrosine: Contraindicated

A

Overactive thyroid. Taking extra tyrosine might increase thyroxine levels, worsening cases of hyperthyroidism. Melanoma.

48
Q

Tyrosine: Caution

A

High doses can cause gastrointestinal upset.

49
Q

Tryptophan

A

• Tryptophan is an essential amino acid.
• Food sources: brown rice, quinoa, pumpkin seeds, oats, bananas, turkey, fish, eggs.

50
Q

Tryptophan: Functions

A

Endrocrine Health
ATP Synthesis

51
Q

Tryptophan: Dosage

A

100-600mg/day [5HTP is usually preferred as it cannot be used for anything other than serotonin and melatonin production].

52
Q

Tryptophan: Drug Interactions

A

Antidepressants, Sedatives, Tramadol, Phenothiazines, Pentazocine, Demerol, Dextromethorphan .

53
Q

Tryptophan: Adverse effects

A

L-tryptophan can cause some side effects such as heartburn, abdominal pain, flatulence, nausea, vomiting, diarrhoea, and a loss of appetite. It can also cause headaches, light headedness, drowsiness, dry mouth, visual blurring, muscle weakness, and sexual problems.

54
Q

Phenylalanine

A

• Phenylalanine is an essential amino acid.
• Food sources: avocado, brown rice, lentils, eggs, fish, meat, soy.

55
Q

Phenylalanine: Functions

A

Endocrine Health
Skin Pigmentation

56
Q

Phenylalanine: Drug Interactions

A

Antipsychotics, neuroleptics.

57
Q

Phenylalanine: Caution

A

Can worsen schizophrenia symptoms.

58
Q

Phenylalanine: Contraindication

A

Phenylketonuria (PKU)

59
Q

Lysine

A

• Lysine is an essential amino acid.
• It is the sister amino acid to arginine (they compete for absorption).
• Lysine dietary sources: quinoa, legumes, tempeh, chicken, eggs, dairy, fish, red meats,.
• Key therapeutic use: Herpes Simplex Virus (cold sores) supplemental L lysine helps to prevent and fight outbreaks. It is more effective when combined with vitamin C.
The virus uses arginine to replicate, so increases in lysine can limit viral replication.

60
Q

Lysine: Functions

A

Herpes Simplex Virus
Structure
Absorption
Glucose Lowering effect

61
Q

Arginine

A

• Arginine is a conditionally essential amino acid.
• Arginine dietary sources: nuts, seeds, seaweed, meat.

62
Q

Arginine: Functions

A

Nitric Oxide (NO)

Functions:
• Arginine is a precursor to Nitric Oxide. Nitric oxide is a vasodilator and subsequently lowers blood pressure.

Therapeutic Uses:
• Hypertension
• Cardiovascular disease (e.g. angina) supports endothelial health
• Sports performance (increases blood flow to muscles)
• Erectile dysfunction

63
Q

Arginine: Drug Interactions

A

Drug interactions: anti hypertensives, GTN spray (angina).

64
Q

Protein Digestibility

A

• Protein digestibility and amino acid composition are said to determine ‘protein quality’
• The digestibility of most animal protein vs. plant protein is variable due to a variety of factors including gut function (i.e. HCl and digestive enzymes), the presence of fibre and some anti-
nutrient factors in plant sources such as phytates and lectins.
• To support the digestibility of plant protein sources, consider soaking, sprouting and fermenting which can lower anti nutrient factors.
• Plant sources also contain fibre, prebiotics, phytonutrients and other ‘qualities’ which can make them a superior choice for everyday healthy eating.

65
Q

Optimising Protein Digestion

A

• Chew thoroughly and avoid drinking with meals.
• Support stomach acid levels:
– Zinc and B6 rich foods (need for HCl production).
– Apple cider vinegar in a little water before meals.
– Bitter herbs and foods before meals (e.g. dandelion, rocket, watercress, artichoke, gentian, barberry bark , goldenseal) These also promote the release of pancreatic juice.
– Use betaine hydrochloride supplements with at least 600mg per capsule. Start with one when starting to eat, before increasing one capsule per meal up to a total of 5 max or until a feeling of warmth. If warm, cut one pill back.

66
Q

Protein Quality: Metabolism and Fermentation

A

• The microbiome contributes to protein metabolism: undigested protein that reaches the colon is fermented, creating toxic metabolites that increase the inflammatory response and
encourages the proliferation of opportunistic pathogens.
• Many of the fermentation products of protein are detrimental to health (e.g. ammonia, amines, sulphides, and N-nitroso compounds), with effects including systemic toxicity, nephrotoxicity , and carcinogenesis .
• Therefore, not overloading the body with protein is an important step. Furthermore, optimising protein digestion is crucial to ensure that as little as possible reaches the colon undigested (see

67
Q

Protein Quality: Amino Acid Composition

A

• To make proteins, a cell must have all the required amino acids available simultaneously; if one essential amino acid is missing, a cell will have to cease making the protein or must dismantle another protein to obtain it.
• If an essential amino acid is supplied in less than the amount needed to support protein synthesis, it is called a limiting amino acid.
• The limiting amino acids are lysine, threonine, methionine, and tryptophan . They are found in the shortest supply from incomplete proteins. For example, beans are low in methionine. This indicates the importance of rotating the sources to provide balance.

Nutrition I - Semester 2 Need To Know (22 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions